1. Field of the Invention
The present invention relates generally to processes and systems for separating oil and water, and more particularly, to oil spill recovery systems.
2. Description of the Prior Art
Commercial oil spill recovery skimmers can recover a fluid stream which typically comprises ten percent by volume oil and water emulsion and ninety percent by volume unwanted free sea water. The oil and water emulsion itself typically contains at least fifty percent, and perhaps as much as ninety percent, water. The condition of the recovered fluid varies greatly depending on the thickness of the oil layer, the state of the seas, the time the spill has weathered, etc. In a typical oil spill recovery vessel having no oil and water separation system located on site all of the recovered fluid is stored in the vessel. Thus the stored fluid may contain up to ninety-nine percent by volume water. If the oil and water could be efficiently separated on site so that the water or a large portion thereof could be returned to the sea and only the recovered oil stored, the oil spill recovery vessels' ability to remain on site and operate for long periods of time could be greatly extended.
The prior art does include systems which have been proposed for the on-site separation of oil and water from recovered oil spill fluids.
One system proposed by Jastram-Werke GmbH of Hamburg, Germany, known as the ORAS system uses an oil/water separator made up of a system of weirs and gates.
U.S. Pat. No. 3,743,095 to Mensing et al. proposes the use of a vortex separator to separate oil from an oil/water mixture which results from oil spills on a body of water.
Robertson et al., "HYDROCYCLONE FOR THE TREATMENT OF OIL-SPILL EMULSIONS", Paper F3 presented at the Second International Conference on Hydrocyclones at Bath, England, Sep. 19-21, 1984, discusses the use of hydrocyclones for the treatment of oil spill emulsions. It deals primarily with the breaking down of the emulsion to remove a portion of the water content thereof.